Critical Congenital Heart Disease Screening

There's an easy way to find out if your baby's tiny heart is beating as it should.

What it is: A noninvasive screening called pulse oximetry (pulse ox for short) that uses a sensor to measure the oxygen levels in your baby’s blood. Low blood oxygen can be a sign of a congenital heart defect, which means the heart has developed abnormally in the womb — one of the ventricles, or walls, has a hole, for instance, or the valves that carry blood aren’t fully formed — and can’t work properly.

When it’s done: Between 24 and 48 hours after your baby is born, a nurse will wrap a sticky sensor around your baby’s right hand before repeating the test on her right foot. The sensor is an infrared light that shines through her little hand just like a flashlight does when it’s held up to your finger. It’s hooked up to a machine that measures how much oxygen is coursing through that tiny circulatory system. The test takes just a few minutes, and there’s no pain involved. Your baby will also get a physical exam at this time. If the pulse-ox results are abnormal, the nurse will repeat the test several times to make sure it’s accurate and get an average reading. If the results raise suspicion, a baby may also have an ultrasound picture of her heart (called an echocardiogram) to confirm the diagnosis of a congenital heart defect.

Why it’s done: About 18 out of every 10,000 babies is born with a condition called critical congenital heart disease — a term that refers to a group of serious heart defects that require treatment shortly after birth, and even pediatric cardiologists — who are specially trained — can miss these problems during an ultrasound or physical exam. In fact, half of these congenital heart defects go undetected until signs show up later, after a baby has left the hospital. Critical congenital heart disease (CCHD), like reversed arteries and veins or a narrow aorta, can be deadly — in fact, CCHD is the cause of death in 3 percent of babies who die during their first year. About 7,200 babies are born in the U.S. every year with CCHD. In a 2009 study done in Sweden, the pulse-ox test diagnosed 92 percent of CCHD babies before they left the hospital.

Is it standard? The CCHD test was added as a “core” condition — a condition that newborn screening is specifically designed to identify — in the Recommended Uniform Screening Panel (RUSP) in September 2011. All states now have mandated use of the pulse-ox test in their newborn screening panels, though some states which require the testing may not yet have fully implemented it.

Should you ask for it: Talk to your doctor to make sure the congenital heart defect test is available at your hospital. Some hospitals do it routinely, though some may not.

What you need to know: Under the Affordable Care Act, most insurance companies started covering CCHD screening in September 2012. If your baby has a congenital heart defect, she will need to see a cardiologist, who may recommend medications or surgery to fix the defect.

From the What to Expect editorial team and Heidi Murkoff, author of What to Expect the First Year. Health information on this site is based on peer-reviewed medical journals and highly respected health organizations and institutions including ACOG (American College of Obstetricians and Gynecologists), CDC (Centers for Disease Control and Prevention) and AAP (American Academy of Pediatrics), as well as the What to Expect books by Heidi Murkoff.